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EPICS release 3.11.6 specific documentation -- Release notes for EPICS 3.11.6

Description: These notes cover the following: (1) directions for switching to production APS release R3.11.6; (2) unbundling of channel access clients; (3) access security; (4) channel access additions; synchronous time support; and (5) description of major differences between R3.11.3 and R3.11.6 Also included is a list of new and/or updated documentation for the program.
Date: June 7, 1994
Partner: UNT Libraries Government Documents Department

Distribution and geochemistry of contaminated subsurface waters in fissured volcanogenic bed rocks of the Lake Karachai Area, Chelyabinsk, Southern Urals

Description: The present investigation is devoted to the study of the distribution and geochemistry of contaminated subsurface waters, beneath the site of temporary storage of liquid radioactive waste known as Lake Karachai. For this purpose a method of hydrogeochemical logging (HGCL) together with standard hydrogeochemical and geophysical methods of uncased hole logging were used. The distribution of sodium nitrate brine plumes in the subsurface was determined by the physical and physico-chemical properties of these brines and by the petrochemical composition of enclosing rocks and the structural setting of the flow paths. The latter is represented by fractures and large faults in the bedrock of volcanogenic and volcanogenic-sedimentary rocks of intermediate-to-basic composition. The volcanogenic rocks are overlain in some places by a thin cover of unconsolidated sediments, i.e., by loams and relatively impermeable silts. Contaminated waters flow-in accordance with the eluvium bottom relief towards local areas of natural (Mishelyak and Techa rivers) and artificial (Novogomenskii water intake) discharge of subsurface waters. The large Mishelyak fault, southwest of Lake Karachai and under fluvial sediments of the Mishelyak, is assumed to significantly influence the flow pattern of contaminated waters, diverting them from an intake of drinking water.
Date: June 1, 1994
Creator: Solodov, I.N.; Belichkin, V.I.; Zotov, A.V.; Kochkin, B.T.; Drozhko, E.G.; Glagolev, A.V. et al.
Partner: UNT Libraries Government Documents Department

Optimization of the Brookhaven ATF inline-injection system utilizing PARMELA

Description: An S-band, RF gun-linac, inline-injection system is being installed at the Brookhaven Accelerator Test Facility. An optimization of the system parameters has been done utilizing the electron beam code PARMELA. We describe the results of this procedure and estimate the brightness of the resulting electron beam. We also incorporate the effects of wake fields into the simulation and evaluate their effects on the beam brightness.
Date: June 1, 1994
Creator: Gallardo, J.C. & Kirk, H.G.
Partner: UNT Libraries Government Documents Department

Department of Energy Programmatic Spent Nuclear Fuel Management and Idaho National Engineering Laboratory Environmental Restoration and Waste Management Programs Draft Environmental Impact Statement; Volume 1, Appendix F, Nevada Test Site and Oak Ridge Reservation Spent Nuclear Fuel Management Programs

Description: This volume addresses the interim storage of spent nuclear fuel (SNF) at two US Department of Energy sites, the Nevada Test Site (NTS) and the Oak Ridge Reservation (ORR). These sites are being considered to provide a reasonable range of alternative settings at which future SNF management activities could be conducted. These locations are not currently involved in management of large quantities of SNF; NTS has none, and ORR has only small quantities. But NTS and ORR do offer experience and infrastructure for the handling, processing and storage of radioactive materials, and they do exemplify a broad spectrum of environmental parameters. This broad spectrum of environmental parameters will provide, a perspective on whether and how such location attributes may relate to potential environmental impacts. Consideration of these two sites will permit a programmatic decision to be based upon an assessment of the feasible options without bias, to the current storage sites. This volume is divided into four parts. Part One is the volume introduction. Part Two contains chapters one through five for the NTS, as well as references contained in chapter six. Part Three contains chapters one through five for the ORR, as well as references contained in chapter six. Part Four is summary information including the list of preparers, organizations contacted, acronyms, and abbreviations for both the NTS and the ORR. A Table of Contents, List of Figures, and List of Tables are included in parts Two, Three, and Four. This approach permitted the inclusion of both sites in one volume while maintaining consistent chapter numbering.
Date: June 1, 1994
Partner: UNT Libraries Government Documents Department

Low-Level Waste Forum notes and summary reports for 1994. Volume 9, Number 3, May-June 1994

Description: This issue includes the following articles: Vermont ratifies Texas compact; Pennsylvania study on rates of decay for classes of low-level radioactive waste; South Carolina legislature adjourns without extending access to Barnwell for out-of-region generators; Southeast Compact Commission authorizes payments for facility development, also votes on petitions, access contracts; storage of low-level radioactive waste at Rancho Seco removed from consideration; plutonium estimates for Ward Valley, California; judgment issued in Ward Valley lawsuits; Central Midwest Commission questions court`s jurisdiction over surcharge rebates litigation; Supreme Court decides commerce clause case involving solid waste; parties voluntarily dismiss Envirocare case; appellate court affirms dismissal of suit against Central Commission; LLW Forum mixed waste working group meets; US EPA Office of Radiation and Indoor Air rulemakings; EPA issues draft radiation site cleanup regulation; EPA extends mixed waste enforcement moratorium; and NRC denies petition to amend low-level radioactive waste classification regulations.
Date: June 1, 1994
Partner: UNT Libraries Government Documents Department

National Metal Casting Research Institute final report. Volume 2, Die casting research

Description: Four subprojects were completed: development and evaluation of die coatings, accelerated die life characterization of die materials, evaluation of fluid flow and solidification modeling programs, selection and characterization of Al-based die casting alloys, and influence of die materials and coatings on die casting quality.
Date: June 1, 1994
Creator: Jensen, D.
Partner: UNT Libraries Government Documents Department

Numerical modeling of the groundwater contaminant transport for the Lake Karachai Area: The methodological approach and the basic two- dimensional regional model

Description: Methodological aspects of the numerical modeling of the groundwater contaminant transport for the Lake Karachay area are discussed. Main features of conditions of the task are the high grade of non-uniformity of the aquifer in the fractured rock massif and the high density of the waste solutions, and also the high volume of the input data: both on the part of parameters of the aquifer (number of pump tests) and on the part of observations of functions of processes (long-time observations by the monitoring well grid). The modeling process for constructing the two dimensional regional model is described, and this model is presented as the basic model for subsequent full three-dimensional modeling in sub-areas of interest. Original powerful mathematical apparatus and computer codes for finite-difference numerical modeling are used.
Date: June 1, 1994
Creator: Petrov, A.V.; Samsonova, L.M.; Vasil`kova, N.A.; Zinin, A.I. & Zinina, G.A.
Partner: UNT Libraries Government Documents Department

LLW Forum summary report, volume 2. No. 2. June 1994

Description: Information provided for each compact and its host state includes: governing body, member states, compact establishment date, current waste management, regulatory and program responsibility, siting responsibility, other involvement, disposal technology, siting, licensing, development costs, and operational date.
Date: June 1, 1994
Partner: UNT Libraries Government Documents Department

What do we really know about the atomic scale structures of nanophase materials?

Description: Robert W. Balluffi has spent a rich research lifetime critically investigating and elucidating the atomic scale defect structures of materials. Now, a new class of ultrafine-grained materials has been created in which such defects exercise a dominant role. The structures of these new nanophase materials, both metals and ceramics, have been investigated over the past several years by a wide range of experimental methods. These studies have included observations by x-ray and neutron scattering, transmission and scanning electron microscopy, Moessbauer, Raman, and positron annihilation spectroscopy, and most recently scanning tunneling and atomic force microscopy and nuclear magnetic resonance. While the experiments have yielded considerable useful information about the structures of nanophase materials on a variety of length scales, much about the local atomic arrangements in the grains and interfaces of these materials remains to be elucidated. The present status of the author`s knowledge of these structures is reviewed and some future research needs and opportunities are considered.
Date: June 1, 1994
Creator: Siegel, R.W.
Partner: UNT Libraries Government Documents Department

A database system for constructing, integrating, and displaying physical maps of chromosome 19

Description: Efforts are underway at numerous sites around the world to construct physical maps of all human chromosomes. These maps will enable researchers to locate, characterize, and eventually understand the genes that control human structure and function. Accomplishing this goal will require a staggering amount of innovation and advancement of biological technology. The volume and complexity of the data already generated requires a sophisticated array of computational support to collect, store, analyze, integrate, and display it in biologically meaningful ways. The Human Genome Center at Livermore has spent the last 6 years constructing a database system to support its physical mapping efforts on human chromosome 19. Our computational support team is composed of experienced computer professionals who share a common pragmatic primary goal of rapidly supplying tools that meet the ever-changing needs of the biologists. Most papers describing computational support of genome research concentrate on mathematical details of key algorithms. However, in this paper we would like to concentrate on the design issues, tradeoffs, and consequences from the point of view of building a complex database system to support leading-edge genomic research. We introduce the topic of physical mapping, discuss the key design issues involved in our databases, and discuss the use of this data by our major tools (DNA fingerprint analysis and overlap computation, contig assembly, map integration, and database browsing.) Given the advantage of hindsight, we discuss what worked, what didn`t, and how we will evolve from here. As early pioneers in this field we hope that our experience may prove useful to others who are now beginning to design and construct similar systems.
Date: June 1, 1994
Creator: Slezak, T.; Wagner, M.; Yeh, Mimi; Ashworth, L.; Nelson, D.; Ow, D. et al.
Partner: UNT Libraries Government Documents Department

A practical high-energy high-luminosity {mu}{sup +} {minus} {mu}{sup {minus}} collider

Description: We present a candidate design for a high-energy high-luminosity {mu}{sup +}{minus}{mu} collider, with E{sub cm} = 4 TeV, L = 3 {times} 10{sup 4}cm{sup {minus}2}s{sup {minus}1}, using only existing technology. The design uses a rapid-cycling medium-energy proton synchrotron, which produces proton beam pulses which are focused onto two {pi}-producing targets, with two {pi}-decay transport lines producing {mu}{sup +{prime}}s. The {mu}`s are collected, rf-rotated, cooled and compressed into a recirculating linac for acceleration, and then transferred into a storage ring collider. The keys to high luminosity are maximal {mu} collection and cooling; innovations with these goals are presented, and future plans for collider development are discussed. This example demonstrates a novel high-energy collider type, which will permit exploration of elementary particle physics at energy frontiers beyond the reach of currently existing and proposed electron and hadron colliders.
Date: June 1994
Creator: Palmer, R. B.; Gallardo, J.; Neuffer, D. V. & Gallardo, J.
Partner: UNT Libraries Government Documents Department

Structural stability of the Weeks Island oil repository

Description: A 3-D finite element analysis was performed to evaluate the stability of the SPR upper and lower oil storage levels at Weeks Island. The mechanical analysis predicted stresses and strains from which pillar stability was inferred using a fracture criterion developed from previous testing of Weeks Island salt. This analysis simulated the sequential mining of the two levels and subsequent oil fill of the mine. The predicted subsidence rates compare well to those measured over the past few years. Predicted failure mechanisms agree with observations made at the time the mine was being modified for oil storage. The modeling technique employed here treats an infinite array of pillars and is a reasonable representation of the behavior at the center of the mine. This analysis predicts that the lower level pillars, at the center of the mine, have fractured and their stability at this time is questionable. Localized pillar fracturing is predicted and implies that the mine is entering a phase of continual time dependent deterioration. Continued and expanded monitoring of the facility and development of methods to assess and predict its behavior are more important now than ever.
Date: June 1, 1994
Creator: Preece, D.S. & Ehgartner, B.L.
Partner: UNT Libraries Government Documents Department

Eutectic bonding of a Ti sputter coated, carbon aerogel wafer to a Ni foil

Description: The formation of high energy density, storage devices is achievable using composite material systems. Alternate layering of carbon aerogel wafers and Ni foils with rnicroporous separators is a prospective composite for capacitor applications. An inherent problem exists to form a physical bond between Ni and the porous carbon wafer. The bonding process must be limited to temperatures less than 1000{degrees}C, at which point the aerogel begins to degrade. The advantage of a low temperature eutectic in the Ni-Ti alloy system solves this problem. Ti, a carbide former, is readily adherent as a sputter deposited thin film onto the carbon wafer. A vacuum bonding process is then used to join the Ni foil and Ti coating through eutectic phase formation. The parameters required for successfld bonding are described along with a structural characterization of the Ni foil-carbon aerogel wafer interface.
Date: June 1, 1994
Creator: Jankowski, A.F.; Hayes, J.P. & Kanna, R.L.
Partner: UNT Libraries Government Documents Department

A comparison of numerical schemes for transport problems

Description: Five finite difference schemes for solving the time-independent, single group transport equation in planar geometry are compared for accuracy and computational speed. We examine in detail two cases: one in which the medium is purely absorbing and another in which isotropic scattering and uniformly distributed sources are also present. In both cases, we find that among the schemes examined, the one based on linear and quadratic finite elements achieves superior accuracy at a given computational cost whenever the zone width is less than a mean free path.
Date: June 1, 1994
Creator: Carson, L. & Ferguson, J.M.
Partner: UNT Libraries Government Documents Department

A{sub 2}Zn{sub 3}As{sub 2}O{sub 2}(A = Ba, Sr): a rare example of square planar zinc

Description: Purpose of this study was to explore synthesis of novel solid-state compounds that could potentially exhibit interesting or useful physical properties. Goal was to extend the classes of compounds A{sub 2}Mn{sub 3}Pn{sub 2}O{sub 2} (A=Sr,Ba; Pn=P,As,Sb,Bi) to include a transition metal other than Mn. High-temperature fluxes were used to produce these new compounds.
Date: June 1994
Creator: Keane, P. M. & Burdett, J. K.
Partner: UNT Libraries Government Documents Department

Comment on ``Simulation of a two-dimensional Rayleigh-Benard system using the direct simulation Monte Carlo method``

Description: In a recent paper, Watanabe, {ital et. al.} used direct simulation Monte Carlo to study Rayleigh-B{acute e}nard convection. They reported that, using stress-free boundary conditions, the onset of convection in the simulation occurred at a Rayleigh number much larger than the critical Rayleigh number predicted by linear stability analysis. We show that the source of their discrepancy is their failure to include the temperature jump effect in the calculation of Rayleigh number.
Date: June 30, 1994
Creator: Garcia, A.L.; Baras, F. & Mansour, M.M.
Partner: UNT Libraries Government Documents Department

Reflectivity of plasmas created by high-intensity, ultra-short laser pulses

Description: Experiments were performed to characterize the creation and evolution of high-temperature (T{sub e}{approximately}100eV), high-density (n{sub e}>10{sup 22}cm{sup {minus}3}) plasmas created with intense ({approximately}10{sup 12}-10{sup 16}W/cm{sup 2}), ultra-short (130fs) laser pulses. The principle diagnostic was plasma reflectivity at optical wavelengths (614nm). An array of target materials (Al, Au, Si, SiO{sub 2}) with widely differing electronic properties tested plasma behavior over a large set of initial states. Time-integrated plasma reflectivity was measured as a function of laser intensity. Space- and time-resolved reflectivity, transmission and scatter were measured with a spatial resolution of {approximately}3{mu}m and a temporal resolution of 130fs. An amplified, mode-locked dye laser system was designed to produce {approximately}3.5mJ, {approximately}130fs laser pulses to create and nonintrusively probe the plasmas. Laser prepulse was carefully controlled to suppress preionization and give unambiguous, high-density plasma results. In metals (Al and Au), it is shown analytically that linear and nonlinear inverse Bremsstrahlung absorption, resonance absorption, and vacuum heating explain time-integrated reflectivity at intensities near 10{sup 16}W/cm{sup 2}. In the insulator, SiO{sub 2}, a non-equilibrium plasma reflectivity model using tunneling ionization, Helmholtz equations, and Drude conductivity agrees with time-integrated reflectivity measurements. Moreover, a comparison of ionization and Saha equilibration rates shows that plasma formed by intense, ultra-short pulses can exist with a transient, non-equilibrium distribution of ionization states. All targets are shown to approach a common reflectivity at intensities {approximately}10{sup 16}W/cm{sup 2}, indicating a material-independent state insensitive to atomic or solid-state details.
Date: June 1, 1994
Creator: Gold, D.M.
Partner: UNT Libraries Government Documents Department

New catalysts for coal processing: Metal carbides and nitrides. Final report, September 11, 1991--September 10, 1994

Description: The main objective of this project was to study transition metal carbides and nitrides as catalysts for hydroprocessing. In particular, the goals were to study the solid-state transformations that occur during synthesis of the compounds using a temperature-programmed method, and to investigate the catalytic properties of the materials for the upgrading of model coal liquids at realistic process conditions.
Date: June 8, 1994
Creator: Oyama, S.T.
Partner: UNT Libraries Government Documents Department

Residual stresses and stress corrosion cracking in pipe fittings

Description: Residual stresses can play a key role in the SCC performance of susceptible materials in PWR primary water applications. Residual stresses are stresses stored within the metal that develop during deformation and persist in the absence of external forces or temperature gradients. Sources of residual stresses in pipe fittings include fabrication processes, installation and welding. There are a number of methods to characterize the magnitude and orientation of residual stresses. These include numerical analysis, chemical cracking tests, and measurement (e.g., X-ray diffraction, neutron diffraction, strain gage/hole drilling, strain gage/trepanning, strain gage/section and layer removal, and acoustics). This paper presents 400 C steam SCC test results demonstrating that residual stresses in as-fabricated Alloy 600 pipe fittings are sufficient to induce SCC. Residual stresses present in as-fabricated pipe fittings are characterized by chemical cracking tests (stainless steel fittings tested in boiling magnesium chloride solution) and by the sectioning and layer removal (SLR) technique.
Date: June 1, 1994
Creator: Parrington, R.J.; Scott, J.J. & Torres, F.
Partner: UNT Libraries Government Documents Department

Implementation of the shower max electron trigger at CDF

Description: The authors have built and installed new electronics which brings the central shower max detector into the CDF Level-2 trigger. By matching a stiff track from the central fast track processor to an associated shower max cluster, this trigger improvement reduces the electron Level-2 cross section by approximately 50% while retaining greater than 85% of real electrons and allows the authors to lower their electron trigger threshold.
Date: June 1, 1994
Creator: Byrum, K.; Dawson, J.; Nodulman, L.; Wicklund, A.B.; Amidei, D.; Burkett, K. et al.
Partner: UNT Libraries Government Documents Department

Allergy arising from exposure to airborne contaminants in an insect rearing facility: Health effects and exposure control

Description: In agricultural crop improvement, yield under various stress conditions and limiting factors is assessed experimentally. Of the stresses on plants which affect yield are those due to insects. Ostrinia nubilalis, the European corn borer (corn borer) is a major pest in sweet and field corn in the U.S. There are many ways to fight crop pests such as the corn borer, including (1) application of chemical insecticides, (2) application of natural predators and, (3) improving crop resistance through plant genetics programs. Randomized field trials are used to determine the effectiveness of pest management programs. These trials frequently consist of randomly selected crop plots to which well-defined input regimes are instituted. For example, corn borers might be released onto crop plots in several densities at various stages of crop development, then sprayed with different levels of pesticide. These experiments are duplicated across regions and, in some cases across the country, to determine, in this instance for example, the best pesticide application rate for a given pest density and crop development stage. In order to release these pests onto crop plots, one must have an adequate supply of the insect pest. In winter months studies are carried out in the laboratory to examine chemical and natural pesticide effectiveness, as well as such things as the role of pheromones in moth behavior. The advantage in field trials is that yield data can be garnered directly. In this country, insects are raised for crop research primarily through the US Department of Agriculture, in cooperation with public Land Grant Universities and, by the private sector agricultural concerns - seed companies and others. This study quantifies the airborne allergen exposure of persons working in a Land Grant University entomology lab were allergy to European corn borer was suspected.
Date: June 1, 1994
Creator: Wolff, D.
Partner: UNT Libraries Government Documents Department

Calorimetric measurement of afterheat in target materials for the accelerator production of tritium

Description: The estimate of afterheat in a spallation target of lead (Pb) or tungsten (W), by calorimetry, is the purpose of this experiment in support of the Accelerator Production of Tritium (APT). Such measurements are needed to confirm code calculations, these being the only practical way of gaining this type of information in a form suitable to aid the design of the APT machine. Knowledge of the magnitude and duration of afterheat resulting from decay of activation products produced by proton bombardment of the target is necessary to quantify APT safety assumptions, to design target cooling and safety systems, and to reduce technical risk. Direct calorimetric measurement of the afterheat for the appropriate incident proton energies is more reliable than the available alternative, which is indirect, based on data from gamma-ray spectroscopy measurements. The basic concept, a direct measurement of decay afterheat which bypasses the laborious classical way of determining this quantity, has been demonstrated to work. The gamma-ray energy given off by the decay products produced in the activation of lead or tungsten with high-energy protons apparently does represent a significant fraction of the total decay energy. A calorimeter designed for measurement of isotopes decaying by alpha emission must be modified to reduce energy lost with escaping gamma rays. Replacement of the aluminum liner with a tungsten liner in the SSC measurement chamber resulted in a 270% increase in measured heat, proving that the energy loss in the earlier (1992) measurements was significant. Gamma-ray measurements are needed to confirm the gamma-ray absorption calculations for the calorimeter to determine the correction for loss of heat due to transmission of high-energy gamma rays through the calorimeter walls. The experiments at BLIP have shown that calorimetry can be a useful tool in measuring the afterheat in APT target materials.
Date: June 1, 1994
Creator: Perry, R.B. & Zucker, M.S.
Partner: UNT Libraries Government Documents Department